1. Field of the Invention
The present invention relates generally to waveguides and more particularly to a polarized mitered corner for square waveguides which provides a match for both orthogonal modes (TE.sub.10 and TE.sub.01) simultaneously.
2. Description of Related Art
Square waveguides are often used in dual polarization applications, since square waveguides can support two orthogonal modes (TE.sub.10 and TE.sub.01) with identical phase velocity. In constructing practical waveguide systems, it is often necessary to provide a bend or corner where two sections of waveguide join at some angle other than a straight line. Well matched bends or corners are often difficult to achieve, due to the complexities involved in changing the direction of propagation within the waveguide system. A right angle bend or corner is one of the most difficult to achieve. Traditionally, a right angle corner is implemented by constructing a mitered corner which provides a diagonally oriented reflecting surface for changing the direction of the propagating electromagnetic energy and causing it to round the corner or bend. Corners other than right angle corners are implemented in the same way.
There can be a great deal of mismatch associated with each corner or bend in the waveguide system. To minimize this mismatch, the traditional mitered corner is carefully tuned by selecting the proper miter size for minimum mismatch. Although this can be done in rectangular waveguide systems which are designed to support a single propagation mode (typically the TE.sub.10 mode), the same is not true for square waveguides designed for dual mode operation.
In square waveguide systems for simultaneously supporting dual propagation modes, the simple mitered corner is less effective. This is largely due to the fact that the TE.sub.10 mode and the TE.sub.01 mode behave differently when reflecting from the mitered corner and inherently require different miter sizes. If the mitered corner is designed for optimal E-plane performance (tuned to the TE.sub.01 mode), it will not have optimal performance for the H-plane mode, and vice versa. The prior art has failed to adequately address this problem.